From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=57616 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PpiZj-0004Xg-L4 for qemu-devel@nongnu.org; Wed, 16 Feb 2011 09:41:52 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PpiZi-0008AL-Fv for qemu-devel@nongnu.org; Wed, 16 Feb 2011 09:41:51 -0500 Received: from mail-qy0-f180.google.com ([209.85.216.180]:49619) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PpiZi-0008A9-8y for qemu-devel@nongnu.org; Wed, 16 Feb 2011 09:41:50 -0500 Received: by qyk29 with SMTP id 29so1541271qyk.4 for ; Wed, 16 Feb 2011 06:41:49 -0800 (PST) Message-ID: <4D5BE217.2020306@codemonkey.ws> Date: Wed, 16 Feb 2011 08:41:27 -0600 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] KVM call minutes for Feb 15 References: <20110215162629.GN21720@x200.localdomain> <4D5B0889.4030303@codemonkey.ws> <20110216143934.GB5770@amit-x200.redhat.com> In-Reply-To: <20110216143934.GB5770@amit-x200.redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Amit Shah Cc: Chris Wright , qemu-devel@nongnu.org, kvm@vger.kernel.org On 02/16/2011 08:39 AM, Amit Shah wrote: > On (Tue) 15 Feb 2011 [17:13:13], Anthony Liguori wrote: > >> On 02/15/2011 10:26 AM, Chris Wright wrote: >> >>> revisit new -> old migration >>> - Amit offers virtio-serial patches and some legwork >>> >> So, to me, migration correctness trumps compatibility. I don't >> think compatibility is useful if it means that a guest may fail >> during migration. We have subsections as a way to support the cases >> where it's safe to migrate to an old version only if a feature is >> not being used or a corner case is not currently happening. This is >> the best way to approach the problem. >> >> If a subsection won't work, that means you want to migrate when >> you're completely sure that migrating will break a guest. That >> doesn't seem reasonable at all to me. >> >> I think in the last discussion on Amit's patches, I had suggested >> that subsections could be used to allow migration when there wasn't >> any queued data. I think this is the best we can do while >> preserving correctness. >> > The only problem is that virtio hasn't been converted over to vmstate, > which is necessary for subsections. > Then it needs to be converted. Regards, Anthony Liguori > Amit > >